Recent work in has demonstrated the plyamidoamine dendrimers, a new type of highly branched dendtiric polymer, can b used to mediate the efficient transfer of genetic material into eukaryotic cell. This polymer has a highly defined structure, is inert and non-immunogenic, and binds nucleic acids of any size or structure in a wide variety of conditions. High efficiency DNA transfer has been mediated to a wide variety of cells in vitro using the dendrimer/DNA complexes. These cells have included airway epithelial cells lines. In addition, preliminary evidence suggests that DNA/dendrimer complexes can transfect lung cells in vivo and that DNA complexed to dendrimers has prolonged persistence in vivo. In addition, the unique ability to alter specific parameters in dendrimer structure allows these molecules to be used as probes to examine particular aspects of the transfection of different types of airway epithelial cells. The central hypothesis of this proposal is that unique forms of dendritic polymers will bind and effectively deliver therapeutic nucleic acid molecules to airway mucosal cells in vivo. This form of gene transfer would be employed for the treatment of airway inflammatory diseases an involve the delivery of different forms of therapeutic nucleic acids to alter a variety of inflammatory events. First, a number of different dendrimers will be produced to determine what alterations in polymer design or the conjugation of the polymers to molecules, such carbohydrates, drugs, antibodies, or synthetic peptides, will allow the efficient targeting and transfer of DNA/dendrimer complexes to specific airway epithelial or inflammatory cells. A well defined model of pulmonary fibrosis will then be employed to test the efficacy of genetic intervention using DNA/dendrimer complexes to prevent the development of fibrosis. This proposal is based on work from my laboratory and also studies from other groups that have documented that dendrimers are easily conjugated to targeting molecules and that conjugated dendrimers can efficiently target radionucleotides to cells in vivo. The results of these studies will provide basic information about gene delivery that should allow further refinements in protocols and agents for endobronchial gene transfer.